Effect of the Structure of Phosphoryl- and Carbonyl-Containing Podands on the Extraction of Lanthanides(III) from Nitric Acid Solutions in the Presence of Ionic Liquid, 1-Butyl-3-methylimidazolium Bis[(trifluoromethyl)sulfonyl]imide

The interphase distribution of lanthanide(III) ions between aqueous solutions of HNO₃ and solutions of tetrabutyldiglicolamide Bu₂C(O)CH₂OCH₂C(O)NBu₂ (1), compounds R₂P(O)CH₂OCH₂C(O)NBu₂, where R = Bu (2), R = Ph (3) and phosphoryl-containing podands R₂P(O)CH₂OCH₂P(O)R \(_{2}^{1}\) , where R = R¹ = Bu (4); R = Bu, R¹ = Ph (5); R = R¹ = Ph (6) in 1,2-dichloroethane and ionic liquid—1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide—has been studied. Extraction of metal ions has been found to increase considerably in the presence of ionic liquid in organic phase. The stoichiometry of the extracted complexes has been determined and the influence of HNO₃ concentration in aqueous phase and the structure of the extractant on the efficiency of metal ions extraction into organic phase has been considered.